The following abbreviations that appear in the ensuing description are defined as follows:                3GPP Third Generation Partnership Project        DCH Dedicated Channel        DL Downlink (Node B to UE)        E-AGCH E-DCH Absolute Grant Channel        E-DCH Enhanced DCH        E-HICH E-DCH HARQ Acknowledgment Indicator Channel        E-RGCH E-DCH Relative Grant Channel        E-RNTI E-DCH Radio Network Temporary Identifier        HARQ Hybrid Automatic Repeat reQuest        HSUPA High Speed Uplink Packet Access        IE Information Element        NBAP Node B Application Protocol        Node B Base station        RNC Radio Network Controller        RNSAP Radio Network Subsystem Application Protocol        RRC Radio Resource Control        SRNC Serving RNC        RL Radio Link        RoT Rise over Thermal        UE User Equipment        UL Uplink (UE to Node B)        VoIP Voice over Internet Protocol        
For 3GPP it has been agreed that there are to be two scheduling methods. These are an Absolute Grant method that uses E-AGCH, and a Relative Grant method that uses E-RGCH. The E-AGCH is a shared downlink channel that is used to provide an absolute limitation on the amount of uplink resources the UE may use for the E-DCH, scheduling how much data the UE can send (data rate) and maximum power. The E-RGCH complements the E-AGCH, and is used to increase or decrease the scheduled rate and/or power the UE sends on the E-DCH as compared to the previous value granted (e.g., granted over the E-AGCH or by a previous command over the E-RGCH). The E-AGCH is sent from only one cell, referred to as the E-DCH serving cell. The E-RGCH may be sent from each cell in an E-DCH Active Set, i.e., E-RGCH is not mandated to be sent from all cells in the E-DCH Active Set. It is left to the Node B implementation for configuring the E-RGCH resource for the UE. The E-HICH is the Hybrid Automatic Repeat Request (HARQ) channel, a physical channel used by the HARQ process to acknowledge transmissions from the user equipment on the E-DCH. The makes the uplink more resilient to signal errors by allowing retransmissions of faulty packets, as requested by the Node B by acknowledgements or negative acknowledgements.
Respecting the E-RGCH, there can be a serving relative grant and a non-serving relative grant on that shared physical channel. Transmitted on the downlink E-RGCH, the serving relative grant is from any cell in the serving E-DCH RL service, and allows the Node B to adjust the granted rate of UE's under its control. Typically, the command for the serving relative grant is “UP”, “DOWN”, or “HOLD”. Also transmitted on the downlink E-RGCH is the non-serving relative grant. This allows neighboring Node B's to adjust the transmitting rate of UE's not under its control (e.g., in neighboring cells under control of the serving Node B) in order to avoid overload situations. Typically, the command for the non-serving relative grant is either “HOLD” or “DOWN”. Multiple non-serving relative grants can be sent to a UE at one time (since there may be multiple neighboring cells under control of different non-serving Node B's), whereas by definition there may be only one serving relative grant sent to a UE at any one time (from its serving cell as scheduled by the serving Node B).
In the current specification the E-RGCH is configured only when the E-DCH is setup, and there is no technique specified to release, configure and reconfigure the E-RGCH in the Node B after the setup of E-DCH, i.e., the Node B is required to use the same E-RGCH configuration until the E-DCH is released, or until the RL is deleted. Conversely, in the case that the Node B does not configure the E-RGCH at E-DCH setup, the Node B will not have the E-RGCH until the E-DCH is released.
As the E-DCH concept is a new feature for 3GPP, prior to this invention there were no satisfactory solutions to the foregoing problems.